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Net Investment Gains (Losses) (Change in Unrealized Gains (Losses) of Available For Sales Securities) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Realized and Unrealized Investment Gains Losses [Line Items]
Unrealized investment gains, before tax	$ 84,474	$ 392,903	$ (1,248,128)
Income tax (expense) benefit	(15,292)	(86,350)	264,325
Noncontrolling interests	2	(2)	(2)
Total change in unrealized gains and losses	69,184	306,551	(983,805)
Debt Securities
Realized and Unrealized Investment Gains Losses [Line Items]
Unrealized investment gains, before tax	83,395	389,839	(1,216,292)
Fixed maturity securities with allowance for expected credit losses
Realized and Unrealized Investment Gains Losses [Line Items]
Unrealized investment gains, before tax	4,428	643	(28,370)
Investment funds
Realized and Unrealized Investment Gains Losses [Line Items]
Unrealized investment gains, before tax	(3,217)	3,989	(2,019)
Other
Realized and Unrealized Investment Gains Losses [Line Items]
Unrealized investment gains, before tax	$ (132)	$ (1,568)	$ (1,447)

X

- Definition

Amount, before tax and after adjustment, of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(19))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 10A
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-10A

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 10A
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-10A

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-11

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